Second grade science project ideas include measuring the rate of mold growth on food, making a lemon battery, experimenting with chlorophyll, making a volcano or seeing what happens when plants are watered with juice or milk. Education.com and ScienceProject.com have many examples of potential second-grade science projects.
ScienceProject.com has a list of ideas for projects that include making a sundial, creating a model of the solar system or investigating a hen's egg. However, details on how to do each project are only available to members.
Project ideas promoted by Education.com, such as using salt to show why the ocean doesn't freeze, mention the required materials for each project and outline a proposed procedure for the student to follow.